I have a 2004 automatic Toyota Corolla 180,500 miles and a 2000 automatic ford ranger with 156,000 miles, I'm not sure if the transmission fluid had ever been changed and I'm wondering if I should try to change it?
Don't go somewhere and flush it...it's too late for that.....I would do the drain and fill method. Drain the transmission fluid. Pour into a container and get a good measurement how much came out, and fill it with exactly how much came out. Drive a couple weeks or 200-300 miles and do it two more times. This gets most of the old fluid out.
I'm in the same boat with my 188k mile '08 Highlander and doing this procedure.
Drain out a small sample. If it's burnt, dark or has metal, do a drain and fill.
DON'T FLUSH THESE TRANSMISSIONS. That will ruin these vehicles.
And don't mix different types of coolants in the transmissions. OEM is best.
You might want to check out the coolant as well.
search the forum for "transmission fluid". You'll get hundreds of answers.
Coolant is new, replaced it like a month ago